Paddle leash

From Trail-Finder -- Dedicated to getting you outside

A paddle leash is used in kayaking to ensure that the paddle and the kayak stay together. These inexpensive pieces of equipment wrap or tie around the center of the paddle on one end and clip to the front bungee cords on the other.

Why?

If you're in whitewater, and you fall out or hit a rock and drop your paddle, without a paddle leash, you may never find your paddle, which can make for a long, unpleasant walk downriver carrying your boat.

On open water, there are two risks. Waves, which will hide a lost paddle from you, and wind, which will blow your boat away from it fast.